*Memos for a string and byte string(bytes and bytearray) functions:
- My post explains count().
- My post explains find().
- My post explains rfind().
- My post explains rindex().
- My post explains ord(), sorted() and reversed().
*Memos for a string and byte string(bytes and bytearray):
str.index() and bytes.index() or bytearray.index() can get the 1st index of the substring and byte substring respectively matched to sub between [start, end), searching from the left to the right (with error if the substring and byte substring don't exist respectively) as shown below:
*Memos:
- The 1st argument is
sub(Required-Type:strforstr.index()or Bytes-like object andintforbytes.index()andbytearray.index()):- It's the substring and byte substring of zero or more characters and bytes respectively.
- Don't use
sub=.
- The 2nd argument is
start(Optional-Type:intor NoneType):- It's a start index.
- If it's not set or
None,0is set. - Don't use
start.
- The 3rd argument is
end(Optional-Type:intor NoneType):- It's an end index.
- If it's not set or
None, the length+ 1is set. - Don't use
end.
- Error occurs if the substring and byte substring don't exist respectively.
<String>:
v = 'grapes peach'
print(v.index('pe')) # 3
print(v.index('pe', None, None)) # 3
print(v.index('pe', 3)) # 3
print(v.index('pe', 4)) # 7
print(v.index('pe', 7)) # 7
print(v.index('pe', 0, 5)) # 3
print(v.index('pe', 7, 12)) # 7
print(v.index('')) # 0
print(v.index('g', 0, 1)) # 0
print(v.index('h', 11, 12)) # 11
print(v.index('PE'))
print(v.index('pe', 8))
print(v.index('pe', 0, 4))
print(v.index('pe', 8, 12))
print(v.index('abc'))
# ValueError: substring not found
v = ''
print(v.index('')) # 0
<Byte String(bytes & bytearray)>:
v = b'grapes peach'
v = bytearray('grapes peach'.encode())
print(v.index(b'pe')) # 3
print(v.index(bytearray(b'pe'))) # 3
print(v.index(b'pe', None, None)) # 3
print(v.index(bytearray(b'pe'), None, None)) # 3
print(v.index(b'pe', 3)) # 3
print(v.index(bytearray(b'pe'), 3)) # 3
print(v.index(b'pe', 4)) # 7
print(v.index(bytearray(b'pe'), 4)) # 7
print(v.index(b'pe', 7)) # 7
print(v.index(bytearray(b'pe'), 7)) # 7
print(v.index(b'pe', 0, 5)) # 3
print(v.index(bytearray(b'pe'), 0, 5)) # 3
print(v.index(b'pe', 7, 12)) # 11
print(v.index(bytearray(b'pe'), 7, 12)) # 11
print(v.index(b'')) # 0
print(v.index(bytearray(b''))) # 0
print(v.index(b'g', 0, 1)) # 0
print(v.index(ord('g'), 0, 1)) # 0
print(v.index(103, 0, 1)) # 0
print(v.index(bytearray(b'g'), 0, 1)) # 0
print(v.index(b'h', 11, 12)) # 11
print(v.index(ord('h'), 11, 12)) # 11
print(v.index(104, 11, 12)) # 11
print(v.index(bytearray(b'h'), 11, 12)) # 11
print(v.index(b'PE'))
print(v.index(bytearray(b'PE')))
print(v.index(b'pe', 8))
print(v.index(bytearray(b'pe'), 8))
print(v.index(b'pe', 0, 4))
print(v.index(bytearray(b'pe'), 0, 4))
print(v.index(b'pe', 8, 12))
print(v.index(bytearray(b'pe'), 8, 12))
print(v.index(b'abc'))
print(v.index(bytearray(b'abc')))
# ValueError: subsection not found
v = b''
v = bytearray(b'')
print(v.index(b'')) # 0
print(v.index(bytearray(b''))) # 0